A Facile Approach Based on Functionalized Silver Nanoparticles as a Chemosensor for the Detection of Paraquat

Abstract

In this study, a simple approach was developed based on imidacloprid stabilized silver nanoparticle (Imida-AgNPs) for the sensitive detection of paraquat pesticide. Experimental parameters were optimized for the synthesis of the proposed sensor. Imida-AgNPs, synthesized under the optimized reaction condition were characterized by UV–Vis spectrophotometer, Fourier transform infrared (FT-IR) spectroscopy and atomic force microscopy (AFM). The Imida-AgNPs were spherical in shape with an average size of 40–70 nm. The stability of Imida-AgNPs was checked towards changes in temperature, time, pH, and salinity. The synthesized Imida-AgNPs were tested as a colorimetric sensor to detect a trace amount of paraquat for the first time. The developed sensor was green, simple, selective and economical. The calibration curve for detection of paraquat was found linear over the concentration range of 20–180 µM. The standard deviation (SD) was found to be 0.0019 µM with relative standard deviation (RSD) of 0.027%. The limit of detection (LOD) and limit of quantification (LOQ) were found to be 6.27 µM and 19 µM respectively. Importantly, the sensor was successfully employed for the detection of paraquat in real samples.